gamedayspx-monitor / model_regr_v2.py
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univariate reg model
2310a6b
import pandas as pd
import numpy as np
from tqdm import tqdm
from sklearn.linear_model import LinearRegression
from sklearn.model_selection import TimeSeriesSplit
from regrCols import model_cols
def walk_forward_validation(df, target_column, num_periods, mode='full'):
df = df[model_cols + [target_column]]
df[target_column] = df[target_column].astype(float)
tscv = TimeSeriesSplit(n_splits=len(df)-1, max_train_size=None, test_size=num_periods) # num_splits is the number of splits you want
if mode == 'full':
overall_results = []
# Iterate over the rows in the DataFrame, one step at a time
# Split the time series data using TimeSeriesSplit
for train_index, test_index in tqdm(tscv.split(df), total=tscv.n_splits):
# Extract the training and testing data for the current split
X_train = df.drop(target_column, axis=1).iloc[train_index]
y_train = df[target_column].iloc[train_index]
X_test = df.drop(target_column, axis=1).iloc[test_index]
y_test = df[target_column].iloc[test_index]
y_train = y_train.astype(float)
model = LinearRegression()
model.fit(X_train, y_train)
# Make a prediction on the test data
predictions = model.predict(X_test)
# Create a DataFrame to store the true and predicted values
result_df = pd.DataFrame({'IsTrue': y_test, 'Predicted': predictions}, index=y_test.index)
overall_results.append(result_df)
df_results = pd.concat(overall_results)
uppers = []
lowers = []
alpha = 0.05
for i, pct in tqdm(enumerate(df_results['Predicted']), desc='Calibrating Probas',total=len(df_results)):
try:
df_q = df_results.iloc[:i]
pred = df_results['Predicted'].iloc[-1]
errors = df_q['IsTrue'] - df_q['Predicted']
positive_errors = errors[errors >= 0]
negative_errors = errors[errors < 0]
# Calculate bounds
upper_bound = pred + np.quantile(positive_errors, 1 - alpha)
lower_bound = pred + np.quantile(negative_errors, alpha)
except:
upper_bound = None
lower_bound = None
uppers.append(upper_bound)
lowers.append(lower_bound)
df_results['Upper'] = uppers
df_results['Lower'] = lowers
elif mode == 'single':
X_train = df.drop(target_column, axis=1).iloc[:-1]
y_train = df[target_column].iloc[:-1]
X_test = df.drop(target_column, axis=1).iloc[-1]
y_test = df[target_column].iloc[-1]
y_train = y_train.astype(float)
model = LinearRegression()
model.fit(X_train, y_train)
predictions = model.predict(X_test.values.reshape(1, -1))
df_results = pd.DataFrame({'IsTrue': y_test, 'Predicted': predictions}, index=[df.index[-1]])
return df_results, model
def calc_upper_lower(pred, df_hist, alpha=0.05):
errors = df_hist['IsTrue'] - df_hist['Predicted']
positive_errors = errors[errors >= 0]
negative_errors = errors[errors < 0]
# Calculate bounds
upper_bound = pred + np.quantile(positive_errors, 1 - alpha)
lower_bound = pred + np.quantile(negative_errors, alpha)
return upper_bound, lower_bound
def seq_predict_proba(df, trained_clf_model):
clf_pred_proba = trained_clf_model.predict_proba(df[model_cols])[:,-1]
return clf_pred_proba